An explosion near the Podkamennaya Tunguska River on June 30, 1908, flattened some 820 square miles of Siberian forest and may have been equal to a atomic bomb nuclear explosion. Over the years there has been a great deal of speculation as to exactly what caused the Tunguska event, but the longstanding theory is a cosmic size impact from an asteroid or comet.
On February 15, 2013, just hours before the asteroid 2012 DA14 was to make its close fly by of Earth, a much smaller meteoroid came down over Russia's Urals region, sparking fear of another Tunguska event.
The impact caused houses to shake, windows to be blown out and cell phones to stop working, as a series of explosions sparked panic in three major cities. In the city of Chelyabinsk, where downtown office buildings were evacuated and hundreds were injured, witnesses said the explosion was so loud that it resembled an earthquake and thunder at the same time, and that there were huge trails of smoke across the sky. Others reported seeing burning objects fall to earth.
Locals reported that the explosion rattled their houses and smashed windows:
“This explosion, my ears popped, windows were smashed… phone doesn’t work,” Evgeniya Gabun wrote on Twitter.
“My window smashed, I am all shaking! Everybody says that a plane crashed,” Twitter user Katya Grechannikova reported.
“My windows were not smashed, but I first thought that my house is being dismantled, then I thought it was a UFO, and my eventual thought was an earthquake,” Bukreeva Olga wrote on Twitter.
Yuri Burenko, head of the Chelyabinsk branch of the Emergencies Ministry, told Reuters. "There have never been any cases of meteorites breaking up at such a low level over Russia before."